Since the last annual report, six additional HIV-positive volunteers were enrolled on the study and eight have completed protocol-directed neurocognitive testing, MR imaging of the brain and MR imaging of the carotids. Enrollment is ongoing. There has been no change in the purpose or scope of this project during the fiscal year. There has been a change in some of the imaging methods. MRS was removed and contrast administration was added to the protocol. In December 2013, The PI role was transferred to Dr Caryn Morse form CCMD in the CC.Dr Avi Nath is the accountable investigator.